This invention relates to electronic devices, and more particularly, to testing electronic devices with wireless communications capabilities.
Wireless electronic devices may include radio-frequency tuners. For example, a wireless electronic device may have a frequency modulation (FM) radio tuner. An FM radio tuner allows an electronic device to selectively receive FM radio signals at specified radio frequencies. FM signals are radio-frequency signals that are generated by varying the frequencies of carrier waves depending on the strength of input signals that are to be transmitted.
FM radio stations broadcast audio material on respective FM radio channels. FM radio channels typically lie at frequencies ranging from 76 MHz to 108 MHz. Numerous FM radio stations broadcast material simultaneously. For example, a first radio channel at 94.9 MHz may broadcast a first set of FM radio signals while a second radio channel at 101.5 MHz simultaneously broadcasts a second set of FM radio signals.
During manufacturing, wireless electronic devices are typically tested for their ability to receive radio-frequency signals. For example, a device with an FM tuner can be tested to evaluate how well the device receives FM radio signals from various FM radio channels. A single-carrier (single channel) FM signal generator is commonly used to test this type of device. The single-carrier FM signal generator generates a test signal for a single radio channel at a time. In testing a wireless electronic device, the device is connected to the single-carrier FM signal generator and a host computer. To test performance at different portions of the FM band, the FM channel of the test signal can be varied while tuning the FM tuner in the device accordingly. While this type of arrangement is helpful in testing basic FM performance, it is unable to accurately simulate real-world conditions in which multiple channels are being broadcast simultaneously. Moreover, because a single-carrier signal generator can only generate one radio channel per test iteration, the signal generator must be reconfigured between each test run to test multiple radio channels.
The additional time required to set up the test equipment for each test channel can be significant when performing tests for a large number of radio channels.
It would therefore be desirable to be able to provide improved methods for testing wireless electronic devices for their ability to receive audio signals at various radio channels.